Device for sampling formation fluids



March 8, 1960 H. M. BUCK nEvxcE FOR sAMPLING FORMATION FLuIns 2 Shieets-Sheet 1 Filed June 5, 1957 March 8, 1960 Filed June 5, 1957 H. M. BUCK 2,927,641 DEVICE FOR SAMPLING FORMATION FLIDS 2 Sheets-Sheet 2 F IG. 4.

INVENTOR. Henry M. Buck,

ATTORNEY.

United States Patent() 2,927,641 DEVICE FOR SAMPLING FORMATION FLUIDS Henry M. Buck, Harris County, Tex.,assignor, by mesne assignments, to Jersey Production Research Company, Tulsa, Okla., a corporation of Delaware Application June 5, 1957, Serial No. 663,754 6 Claims. (Cl. 166-64) This invention relates to devices for testing earth formations through which a well has been drilled, and more particularly to devices for obtaining representative samples of earth formation fluids.

In connection with operations directed to the discovery and production of petroleum, it is often desirable to obtain samples of formation iuids from selected subterranean earth formations. In this connection, it is undesirable to utilize samples brought to the earths surface by natural flow or by pumping, inasmuch as there is inevitable separation of gas and oil brought about by changes in the pressure and temperature of the formation fluid as it rises to vthe earths surface. Manifestly, this situation is undesirable when it is contemplated to study the viscosity of the formation uids under the pressure and temperature conditions prevailing in the reservoir, to analyze the hydrocarbon content of the earth formation fluid or to study the gas-oil ratio thereof.

For the purpose of obtaining representative samples of earth formation fluids in the conditions under which they are found in the reservoir, various and sundry devices have been devised in the past. Examples of the prior art may be found in U.S. Patent No. 2,632,512 to P. E. Chaney et al. and U.S. Patent No. 2,589,606 to T. B. Dunn. A common failing of prior art devices such as exemplified in the aforecited patents is that they require a wire line for the purpose of lowering the sampling apparatus to the formation from which fluid is to be obtained and for the purpose of bringing the apparatus back to the eaiths surface. The use of a wire line often is undesirable or infeasible, particularly at offshore locations where a stable operating platform is very difficult and expensive to obtain.

Accordingly, one object of this invention is to provide an improved bottom-hole fluid formation sampler for obtaining earth formation samples representative of liuids under reservoir conditions.

Another object is to provide a bottom-hole fluid formation sampler adapted for use independent of a wire line or auxiliary retrieving apparatus.

Other objects and features of this invention will become apparent upon consideration of the following detailed description thereof when taken in connection with accompanying drawings wherein:

Fig. l is a cross-sectional view of a preferred embodiment of the present invention; f

Fig. 2 is a view of a portion of the apparatus shown in Fig. l with certain of the component parts thereof in their actuated position to more perspicuously illustrate the operation of the apparatus; and

Fig. 3 is a cross-sectional view taken along section 3 3 of Fig. l.

Fig. 4 illustrates a modification of the apparatus shown in Fig. 1.

In accordance with one aspect of the invention, a sampling chamber is provided within the casing of a sonde adapted for insertion in the tubing of a producing well or the drilling pipe of a drilling rig. The sampling chamber is sealed from the exterior of the sonde by means. of a frangible or perforable disc or diaphragm adapted to be perforated by a spear-like member positioned above the diaphragm. A iiexible annular sealing member is provided, affixed to the casing of the sonde and adapted to be restrained against the exterior surface thereof so that uid-ow is possible around the exterior of the sonde.

. check valve housing. As mentioned, housing sections 77 and 85 are screw-v firice member is adapted to contact the inner surface ofthe v tubing or casing to prevent uid passage between the tubing and the housing. Actuating means is provided for the purpose of simultaneously releasing` the sealing member and puncturing the disc so that fluids around. the sonde will be admitted to the sampling chamber and so that the upward pressure of fluids against the sealing members will bring the sonde to the earths surface. A one-way check valve is provided for the purpose of sealing the sampling chamber as soon as the pressure within the sampling chamber is substantially equal to the pressure of the uids external to the sonde and to maintain the fluid in the chamber under the pressure found at the earth formation from which it was obtained.

With reference 'now to the drawings, and particularly to Figs. l and 3, there is shown a sonde 7 within a tubing comprising tubing sections `1 and 23 connected together by a collar 25. The housing for the sonde comprises four sections designated 9, 39, 77, and 85, which are screwthreaded at the mating abutting ends thereof so as to be coupled together in end-to-end relationship in the order specified above. If desired, more-or less housing sections may be utilized in accordance with design requirements. Housing section 85 includes a sampling chamber 101, la check valve housing 95, and orifice 91. The check valve includes a ball 93 adapted to seal the opening of orice 91 and a coil spring 9'7 for the purpose of normally biasing the metal sphere or ball 93 against the opening of orifice 91. Coil spring 97 should be just strong enough to seal the chamber 101 when the pressure external to the chamber is less than a predetermined amount greater than the pressure within the chamber, conveniently 20 pounds per square inch. A plurality of openings 99 are provided in the check valve housing to permit free Huid llow between the chamber 101 and the interior of the threaded together; this provides a second chamber 80, having a plurality of openings 79 to the exterior of housing section 77. Within the second chamber and screwthreaded into housing section 85, is a small nut 83, the purpose of which is to hold a frangible or rupturable disc 87 for sealing the outer opening of orice 91.' Nut 83 has a central bore, the function of which is to provide free fluid communication between the second chamber 80 and orifice 91 when rupturable disc 87 has been pierced. Housing sections 39 and 77 define a third chamber 64, one purpose of which is to house actuating apparatus for rupturing disc 87. A spear-like member 63 is provided which extends through the upper part of housing section 77 into chamber 80 and which is positioned so as to pass through bore 89 of nut 83 to pierce disc 87.

For the purpose of bringing the sonde to the earths surface under the impetus of upwardly flowing uids, there is provided a flexible annular member 35, which is secured to the exterior of the sonde housing by the abutting edges of housing sections 9 and 39. As shown, the flexible member 35 may be constructed so as to t around a reduced section of housing section 9 and may be secured by screw-threading together the male and fe male portions of housing sections 9 and 39. Flexible member 35 conveniently may be a cup washer of stand-` flexible member may conveniently be made of neoprene or other oil resistant material.

In order to permit free downward passage of the sonde through the tubing when the sonde is inserted. into the tubing, the flexible member is held near or against the side of the sonde housing. This is accomplished by an annular restraining means or retaining ring 37 which tits over the lower portion of the flexible member so as to hold it near or against the side of the housing. The retaining ring is supported by one or more cross-arms 43, secured to a central rod 4S which extends downwardly through the center of the chamber 64, preferably on the longitudinal axis thereof. Central rod 45 is integral with spear-like member 63.

A passageway for the rod 45 is provided by a bore drilled through the upper wall of housing section 39 and through a downwardly-extending member 4S, which encloses the lower end of rod 45 and the upper end of member 63. Downwardly-extending member 48 holds u sphere or ball 53 in engagement with the lower end of rod 45 (note that the diameter of rod 45 is greater than diameter of spear-like member 63); thus sphere or ball 53 supports the rod 45 and the cross-arm 43.

Enclosing the downwardly-extending member 43 is a cage 51, which is normally biased in a downward direction by spring 49. The lower end of rod 45 and the cage 51 are arranged in the upper end of chamber 64. Sealing means 56 is provided to afford a fluid-tight seal between the exterior of the housing and the chamber 64. Cage 51 abuts against a shoulder extending from member 48 to limit the downward movement thereof. A hollow screw-threaded shaft 57 is positioned within chamber 64 for rotational movement therein, the shaft 57 enveloping spear-like member 63 and being supported by the upper end of housing section 77. As shown most perspicuously in Fig. 3, shaft 57 is driven by rotation of ratchet gear 69. Rotation of the ratchet gear is effected by apparatus including a ratchet dog 73. The ratchet dog is pivotably supported von arm 65, which is supported by and adapted to rotate about shaft 57. lt should be` noted that only approximately the upper half of shaft 57 is screw-threaded, the lower portion having a relatively smooth external surface. A tension spring 66 is connected between hooks on arm 65 and the interior of chamber 64 so as to tend to bias arm 65 for counterclockwise rotation, as viewed in Fig. 3. A solenoid 67 is secured to the inner wall of housing member 39, the armature thereof being connected to arm 65 by an extension 68thereon so as to restrict counterclockwise movement of arm 65 brought about by spring 66, and further to rotate arm 65 clockwise when the actuating coil of solenoid 67 is energized. One electric terminal of the coil of solenoid 67 is connected to the housing and the other temiinal is connected to electric conductor 33.

As mentioned above, the upper end of shaft 57 is screw-threaded. For the purpose of forcing cage 51 upwardly so that ball 53 may be forced outwardly from rod 45 by the downward Vpressure of the rod, a tripping member 61 is provided. Tripping member 61 is in screw-threaded engagement with shaft 57 and is restrained against rotation by a groove within a member 59, which is fastened to theV side of the chamber 64. When the solenoid 67 is repetitively energized, ratchet gear 69 will rotate shaft 57 and the tripping member 61 will move upwardly. Tripping member 61 in time will force cage 51 upwardly against the restraining influence of spring 49 so that sphere or ball 53 will move outwardly when cage 51 isrmoved upwardly a sucient distance.

For the purpose of periodically energizing solenoid 67 as the housing moves through the tubing, there is provided an electrical energy source 13 which may be an ordinary dry battery. Energy source 13 is housed in a chamber 11 within housing section 9. A Huid-tight access port (not shown) may be provided for the purpose or'. replacing the-battery from time to time, as required.

One terminal of the battery is grounded to the housing and the other terminal is connected to an electrical conductor 3. Conductor 3 passes from chamber 11 through a bore 5 within the housing section 9 to an electrical switch l27 having contacts 29 and 31. Contact 3l is connected to solenoid 67 by means of an electric conduit 33, which passes through bore 33a, through chatnber 42, through the wall of chamber 64, and through chamber 64 to the terminal of solenoid 67. Electric switch 27 is actuated by an apparatus including a roller i3* pivotably supported by arm 15 and housing section 9, and having a connecting rod 21 which is connected to the switch arm. Coil spring 16 biases pivot arm 15 outwardly from the housing so that roller 19 will be in contact with the inner surface of the tubing or of the collar 25. As can be seen in Fig. l, when the roller i9 is in contact with the inner surface of the tubing, electrical contacts 29 and 31 will be disengaged; when roller 19 is forced into the annular groove formed by the tubing sections and the collar 25 as shown in Fig. l, the contacts 29 and 31 will be brought into engagement to complete the electrical circuit between battery 13 and solenoid 67 to momentarily energize the coil of the solenoid.

Manifestly, other types of actuating devices may be utilized, such as shown in Fig. 4. Movable switch contact S is mounted on a rod 169 which is biased into engagement with cam ill by spring 113. The rod slides in a hole in member which is supported on arm i5. Contact 167 also is atiixed to'arm 15. Cam 111 is connected to roller member i9 so as to rotate therewith. The cam actuated switch will momentarily close to energize solenoid 67 upon every revolution of the roller member while it is rolling along the interior surface of the tubing.

For the purpose of providing a certain amount of frictional opposition to downward movement of spear-like member 63 and also to provide a fluid-tight seal between chambers 64 and S0, there is provided an O-ring 75 within the upper wall of housing section 77.

in operation, the apparatus described is inserted into a tubing or drill pipe and allowed to move freely in a downward position. inasmuch as the flexible member or cup washer 35 is restrained by ring 37, the instrument can move freely downwardly in spite of upward uid flow of substantial magnitude. As the instrument moves downwardly, roller 19 will periodically slip into the annular groove formed by the collar 25 and the tubing sec tions connected thereby. Contact members 29 and 31 will thereupon close to energize solenoid 67. Successive closures of the electric switch will thus repetitively energize solenoid 67 to rotate ratchet gear 69 and shaft 57. Rotation of shaft 57 will move tripping member 61 upwardly until cage 51 is pushed upwardly enough to allow ball 53 to move to the right. As the instrument passes down the bore hole, the pressure exerted on the exterior thereof will increase; since the pressure within chamber 64 remains at atmopsheric pressure, a differential pressure will exist between the exterior of the housing and chamber64. By virtue lof thedilerential pressure between the exterior of the housing and chamber 64, rod 45 will be driven'downwardly, releasing annular flexible member 35 and driving spear-like member 63 downwardly to rupture disc 87. The differential pressure existing between chamber 101 and the exterior of the housing will force ball 93 downwardly as shown in Fig. 2. Fluid will flow through ports 79, bore S9, orifice 9i, past the check valve and through ports 99 into sample chan ber 10i. Annular member 35 being released will prevent uid flow upwardly around the instrument so that the housing will begin to move upwardly. As soon as the differential pressure between the exterior' of the housing and chamber 101 drops below a predetermined magnitude, conveniently 20 pounds per square inch, ball 93 will be forced upwardly by spring 97 to close the checlf. val vc, thus preventing further entry of uid into chamber 101. When the sonde reaches` the well head, it maybe angina:-

retrieved. If desired, housing section 85 may be removed and sent to a laboratory for analysis and a duplicate unit screw-threaded on to the sonde 7 so that the sonde may be put to immediate use.

The depth at which annular member 35 is released is determined by the number of energzations of solenoid 67, and the ratio of the number of teeth on ratchet gear 69 to the threads per inch on shaft 57. To determine the depth at which the annular member 35 is to be released, the number of pulses that are required to trip the latching mechanism for various initial positions of tripping member 61 can be determined experimentally. The number of collars in the tubing string can be determined or may be known beforehand. The tripping member 61 will then be positioned on the threaded shaft to trip cage 51 when solenoid 67 has been energized a numberA of times equal to the number of collars down to the desired depth. When a cam-actuated switch which will close upon every revolution of the roller member is used to energize the solenoid winding, a similar procedure will be followed, since the number of revolutions made by the roller member in traversing the tubing to a desired depth can be determined. t

Manifestly, the objects set forth above are achieved by the invention described. The apparatus may be used at any location without the necessity for a wire line or other retrieving device. The apparatus may be used in any location whether ashore or offshore, and the usual requirement of a stable platform is not at all necessary. The invention is not to be restricted to the specific structural details, arrangement of parts, or circuit connections herein set forth, as various modifications there# of may be effected without departing from the spirit'and scope of this invention.

I claim:

1. Apparatus for obtaining a sample of upwardly moving fluids at a predetermined depth in a borehole traversed by a tubing comprising a plurality of sections joined together end-to-end by collar means, said apparatus comprising: a substantially cylindrical housing adap-ted to be inserted within said tubing; a sample chamber in said housing; a second chamber within said housing in iiuid communication with the exterior of said housing; an orifice for providing uid communication between said sample chamber and .said second chamber; spring biased check valvel means within said sample chamber sealing the opening ofvsaid orifice into Asaid sample chamber and adapted to be opened by iiuid pressure in said second chamber; aI rupturable disc within said secondchamber sealing the opening of said orifice into said second chamber; a third chamber within said' housing; a hollow threaded shaft within saidthird chamber; a pointed, spear'- like member within said threaded shaft and extending into said second chamber, said spear-like member being positioned to rupture said disc when -driven a predetermined distance into said second'ch'amber; an annular'flexible member secured to the exteriorof'said housing', said an# nular flexible member being adapted to normally contact the inner surfaceof said tubing to prevent fluid passage between said tubing and said housingjrestraining means for holding said fiexibleannular means away from said tubing to permit fiuid flow around said housing; actuating means operatively associated with said spear-like member including a rod extending into said third chamber, connected to said restraining means and responsive to differential pressure .between the exterior andinterior of said third chamber to be drivenl away from a first position thereof whereat said restraining means holds said flexible annular member away from said tubing to a second position whereatsaid restraining means releases said exible annularmember to contact said tubing, and said rod drives said spear-like member at least said predetermined' distance into said second chamber; trippable latchy means "for holding said piston means in said first positionthereof until said latch means istripped; vtripping nians'for said trippable latch means having a threaded bore, said tripping means being adapted to move lin a direction to trip said latch means, said threaded shaft being adapted to engage said threaded bore to move said tripping means longitudinally therealong by rotation ofv said threaded shaft; a ratchet wheel connected to said shaft to rotate said shaft; electromagnetically actuable means for rotating said ratchet wheel through a predetermined angle upon every actuation thereof so as to move said tripping means in a direction to trip said latch means; an electro magnet for actuating said electromagnetically actuable means upon energization thereof; current source means; movement measuring means for measuring movement of said housing through said tubing; and means actuated by said movement measuring means for momentarily coupling said current source means to said electromagnetV means for repetitively energizing said electromagnetically actuable means as said housing travels through said tubing. 2. Apparatus for obtaining a sample of upwardly moving uids at a predetermined depth in a borehole traversed by a tubing comprising a plurality of sections joined together end-to-end by collar means, said apparatus-comprising: a generally cylindrical housing adapted to be insertedwithin said tubing; a sample chamber in said housing; a second chamber within said housing in fluid comv munication with the exterior of said housing; an orifice for providing fluid communication between said sample chamber and said second chamber; spring biased check valve means within said sample chamber sealing the opening of said orifice into said sample chamber and ladapted to be opened by fluid pressure in` said second chamber; a rupturable disc within said second chamber sealing the opening of said orifice into said second chamber; a third chamber within said housing; a hollow threaded shaft within said third chamber; a pointed, spearlike member within said threaded shaft and extending into said second chamber, said spear-,like member being positioned to rupture said disc when driven a predetermined distance into said second chamber; an annular ilex-V ible member secured to the exterior of said housing, adapted to normally contac-t'the inner surface of said tubing to prevent fluid passage between said tubing and said housing; restraining means for holding said iiexible annular member away from said tubing to permit uid iiow around said housing; actuating means operatively associated with said spear-like member including a rod vextending into said third chamber, connected to said restraining means and responsive to differential pressure between the exterior and interior of said third chamber to be driven `away from a first position thereof whereat 4said restraining means holds said fiexible annular member away from said tubing to a second position whereat said restraining means releases said flexible annular member and said rod drives said spear-like member at least said predetermined distance `-into said second chamber; trippable latch means for holding said piston` means in said first position thereof; and means including means for measuring movement of said housing through -said tubing adapted to trip said trippable latch means to release said piston means upon traversal of said housing through a predetermined length of said tubing.

3. Apparatus for obtaining a' sample of upwardly moving fluids at a predetermined depth in a borehole traversed by a tubing comprising a plurality of sections joined'together end-to-end by collar'means, said apparatus comprising: a generally cylindrical housing adapted to beinserted within said tubing; a sample chamber in said housing; a second chamber within said housing in fiuid communication with the exterior of said housing; an orifice for providing fluid communication between said sample chamber and said second chamber; spring biased check valve means within said sample chamber sealing the opening of said orifice into said samplegchamber and adapted. to be opened by fluid pressure in 4said ,second chamber; arupf',

turable disc within said second chamber sealing the open-` ing of said orifice into said second chamber; a third chamber within said housing; a hollow threaded shaft within said third chamber; a pointed, spear-like member within said `threaded shaft extending into said second chamber, said spear-like member being positioned to rupture said disc when driven a predetermined distance into said second chamber; an annular flexible member secured to the exterior of said housing, said exible annular member being adapted to normally contact the inner surface of said tubing to prevent fluid passage between said tubing and said housing; restraining means connected to said spear-like member, for holding said iiexible annular member away from said tubing to permit iiuid iiow around said housing; and means including means for measuring movement of said housing through said tubing connected to said restraining means for releasing said fiexible annular member and simultaneously driving said spear-like member at least said given distance into said sample chamber upon traversal of said housing through a predetermined length of said tubing.

4. Apparatus for obtaining a sample of upwardly moving uids at a predetermined depth in a borehole traversed by a tubing comprising a plurality of sections joined together end-to-end by collar means, said apparatus comprising: a generally cylindrical housing adapted to be inserted within said tubing; a sample chamber in said housing; a second chamber within said housing in uid communication with the exterior of said housing; an orifice for providing uid communication between said sample chamber and said second chamber; spring biased check valve means within said sample chamber sealing the opening of said orifice into said sample chamber and adapted to be opened by uid pressure in said second chamber; a rupturable disc within said second chamber sealing the opening of said orifice into said second chamber; a third chamber within said housing; a hollow threaded shaft within said third chamber; a pointed, spear-like member within said threaded shaft extending into said second chamber, said spear-like member being positioned to rupture said disc when driven a predetermined distance into said second chamber; an annular flexible member secured to the exterior of said housing, said flexible annular member being adapted to normally contact the inner surface of said tubing to prevent iiuid passage between said tubing and said housing; restraining means for holding said flexible annular member away from said tubing to permit fluid flow around said housing; actuating means integral with said spear-like member connected to said restraining means and responsive to differential pressure between the exterior and interior of said third chamber to be driven away from a rst position thereof whereat said restraining means holds said exible annular member away from said tubing to a second position whereat said restraining means releases said iiexible annular member and drives said spear-like member at least said predetermined distance into said second chamber; trippable latch means for holding said piston means in said first position thereof; and means including means for measuring movement of said housing through said tubing adapted to trip said trippable latch means upon traversal of said housing through a predetermined length of said tubing. Y

5. Apparatus for obtaining a sample of upwardly moving fiuids at a predetermined depth in a bore-hole traversed by a tubing, said apparatus comprising: a housing adapted to be inserted Within said tubing, said housing including a sample chamber having an opening to the exterior of said housing; a spring-loaded check valve closing said opening, said check valve being adapted to be opened byuid pressure applied from the exterior of said housing and closed when the differential pressure'across said check valve is less than a predetermined magnitude; a disc seal isolating said check valve from fluids external to said housing; normally restrained puncturing means in said housing adapted `when released to puncture said disc 75,

seal to open said check valve and permit tiuid ow from the exterior of said housing into said chamber; flexible annular means attached to said housing to normally engage the inner surface of said tubing to prevent fluid ow around said housing; restraining means connected tosaid spear-like member, forholding said exible annular means against the exterior of said housing to permit downward passage of said apparatus through said tubing; and means operatively associated with said restraining means, responsive to passage of said housing through a predetermined length of said tubing for releasing said restraining means to prevent uid passage around said housing and for concomitantly releasing said puncturing means.

6. Apparatus for obtaining a sample of upwardly moving fluids at a predetermined depth in a bore-hole traversed by a tubing comprising a plurality of sections joined together end-to-end by collar means, said apparatus comprising: a generally cylindrical housing adapted to be inserted within said tubing; a sample chamber in said housing; a second chamber within said housing in fluid communication with the exterior of said housing; an orifice for providing fluid communication between said sample chamber and. said second chamber; spring biased check valve means within said sample chamber sealing the opening of said orifice into said sample chamber and adapted to be opened 4by fiuid pressure in said second chamber; a rupturable disc within said second chamber sealing the opening of said orifice into said second chamber; a-third chamber within said housing; a hollow threaded shaft within said third chamber; a pointed, spearlike4 member within said threaded shaft and extending into said second chamber, said spear-like member being positioned to rupture said disc when driven a predetermined distance into said second chamber; an annular flexible member secured to the exterior of said housing,

said annular tiexible member being adapted to normally contact the inner surface of said tubing to prevent fluid passage between said tubing and said housing; restraining means for holding said exible annular member away from said tubing to permit fluid flow around said housng; actuating means including a rod integral with said spear-like member and extending into said third chamber, connected to said restraining means and responsive to differential pressure between the exterior and interior of said third chamber to be driven away from a first position thereof whereat said restraining means holds said flexible annular member away from said tubing to a second position Whereat said restraining means releases said fiexible annular memberV and said rod drives said spear-like member at least said predetermined distance into said second chamber; trippable latch means for holding said piston means in said first position thereof; tripping means for said trippable latch means, said tripping means having a threaded bore and being adapted to move in a direction to trip said trippable latch means, said threaded shaft being adapted to threadedly engage said threaded bore to move said tripping means longitudinally along said shaft by rotation of the latter; and means including means for measuring movement of said housing through said tubing `for rotating said threaded shaft in accordance with movement of said housing through said tubing to move said tripping means toward said trippable latch means to trip said latch means upon traversal of said housing through a predetermined length of said tubing.

References Cited in the file of this patent UNITED STATES PATENTSV 2,147,983 Lindsly Feb. 21, 1939 2,589,606 Dunn Mar. 18, 1952 2,632,512 Chaney et al. Mar. 24, 1953 2,725,283 Mounce et al Nov. 29, 1955 2,728,397 Ruska Dec. 27, 1955 2,776.564 Montgomery et al. Ian. 8, 1957 2,783,64@ Rumble Mar. 5, 1957 

